A parallel beam of monochromatic light of wavelength 500nm is incident normally on a perfectly absorbing surface. The power through any cross- section of the beam is 10 W. Find (a) the number of photons absorbed per second by the surface and (b) the force exerted by the light beam on the surface.

A parellel beam of monochromatic light of wavelength 500 nm is incident normally on a perfectly absorbing surface. The power through any cross section of the beam is 10 W. Find (a) the number of photons absorbed per second by the surface and (b) the force exerted by the light beam on the surface.

A parallel beam of monochromatic light of frequency v is incident on a surface. Intensity of the beam is I and area of the surface is A. Find the force exerted by the light beam on the surface for following cases– (i) the surface is perfectly absorbing and the light beam is incident normally on it. (ii) the surface is perfectly reflecting and the light beam is incident normally. (iii) the surface is perfectly absorbing and the light beam is incident at an angle of incidence theta . (iv) the surface is perfectly reflecting and the light beam is incident at an angle of incidence theta .

A parallel beam of white light is incident normally on surface which absorbs 70% of the incident light and reflects the rest. If incident beam has power of 40 W , then what will be the magnitude of force exerted by the light on this surface ?

A plate of mass 10g is in equilibrium in air due to the force exerted by a light beam on the plate. Calculate power of the beam. Assume that the plate is perfectly absorbing.

There is a parallel beam of light of larger aperture . Let I be the intensity of light . Perfectly reflecting sphere of radius r is kept in the path of this parallel beam . Find the force exerted by the light beam on sphere .

(a) A parallel beam of monochromatic light of wavelength 500 nm is incident normally on a perfectly absorbing surface. The power through any cross section of the beam is 10 W. Find (i) the number of photons absorbed per second by the surface and the force exerted by the lilght beam on the surface. (a) Radiation of wavelength 200 nm, propagating in the form of a parallel beam, fall normally on a plane metallic surface. The intensity of the beam is 5 mW and its cross-sectional area is 1.0 mm^(2) . Find the pressure exerted by the radiation on the metallic surface if the radiation is completeley reflected. (c) A parallel beam of monochromatic light of wavelength 663 nm is incident on a totally reflecting plane mirror. The angle of incidence is 60^(@) and the number of photons striking the mirror per second is 1.0xx10^(19) . Calculate the force exerted by the light beam on the mirror. (d) A beam of white light is incident normally on a plane surface absorbing 70%) of the light and reflecting the rest. If the incident beam carries 10 W of power, find the force exerted by it on the surface.

Light with intensity 20 W / cm^2 is falling along the normal on a surface , which completely abssorbs the light area of the surface is 25 cm^2 find the average force exerted y light on this surface in one hour .

A parallel beam of monochromatic light of wavelength 663 nm is incident on a totally reflecting plane mirror. The angle of incidence is 60^@ and the number of photons striking the mirror per second is (1.0 xx (10^19)) . Calculate the force exerted by the light beam on the mirror.